Measurement and modeling of optical performance of wire grids and liquid-crystal displays utilizing grid polarizers

We studied the optical performance of a reflective wire-grid polarizer designed for visible light. The polarizer reflects E polarization and transmits H polarization with low losses. The studies of transmission and reflectivity of nonpolarized and polarized light from single grids and stacked grids show that the optical performance of wire-grid polarizers can be adequately described by representing the polarizer as an effective uniaxial medium with anisotropic absorption. The description facilitates the incorporation of the polarizers in modeling procedures widely used in the design of liquid-crystal devices. We present the modeling and measurement results of twisted-nematic devices with wire-grid polarizers serving simultaneously as reflective polarizers, alignment layers, and back electrodes. The application of wire-grid polarizers for reflective liquid-crystal devices provides brightness enhancement, high contrast ratio at wide viewing angles, and elimination of viewing parallax.